Interval switch



Feb. 3, 1948. G. SPEER 2,435,370

INTERVAL SWITCH Filed Dec. 18, 1944 2 Sheets-Shet 2 INVENTOR.

ATTCI R N EYS Patented Feb. 3, 1948 UNITED STATES PATENT OFFICE This invention appertains to an interval switch control for electrical circuits, and has for one of its several objects, the provision of a noveland compact assembly of simple switching devices, which are cooperatively associated to controlan electrical circuit, such as a house lighting circuit, for its manual activation and cut-off over an unpredetermined period of time in a usual manner, and for its manual activation and automatic cut-off over comparatively short periods of time.

Another object of the invention is to provide an electrical switch mechanism of this character, which is constructed and arranged in a manner that it may readily be substituted for the ordinary wall, lamp base, or lighting fixture, etc., typesof electrical switches, without necessitating the installation of additional wiring.

Generally, the invention is comprised in a double pole, double throw, electrical switch, which in its on position, connects an electrical device, such as an electric lamp, or lamps, with a power line for the activation of the device or lamp in a usual manner and for the operation of the same over an indeterminate period of time,

and, in its ofifposition, connects the power line with a manual switch, preferably of the pushbutton type, which, in turn, when actuated, temporarily connects the power line with the device or lamp through a relay and a thermostatic switch, the relay operating to shunt the current in the power line about the manual switch for the continued activation of the device or lamp, until the thermostatic switch acts to open the circuit on the device or lamp and the relay, the latter switch being adjustable to vary the time period for its operation to break the circuit between the power line and the device or lamp.

With the foregoing objects and advantages in view, the invention resides in the certain new and useful combination, construction, and arrangement of parts and instrumentalities, as will be hereinafter more fully described, set forth in the appended claims, and illustrated in the accompanying drawings, in which:

Figure l is a plan view of the interval switch, in accordance with the invention, .an outlineof a wall switch plate being shown in hantom lines;

Figure 2 is aside elevatiompartly sectioned through the line 2-2 on Figure 1, looking in they direction of the arrows;

Figure 3 is a cross sectional view taken through the line 3-3 on Figure 1,-1ooking in the direction or the arrows; a

3 Claims. (01. 171-417) Figure 4 is a partially disassembled elevation of the side opposite that shown in Figure 2, the same being partly sectioned through the line 4-4 on Figure 1, looking in the direction of'the arrows;

Figure 5 is a plan view of the bottom part or section of the switch structure;

Figure '6 is a plan view of the top part or section of the switch structure, partially disassembled to show the position of the contacts and terminals Figure 7 is a wiring diagram of the switch, with the relay coils and the heating coil, or resistance, in series with-eachother and in shunt with the lamp; and

Figure 8 is a view similar to that of Figure '7, butshowing the relayand heating coils, and'the lamp, in series circuit.

In Figure 7 and Figure 8, the switches are both shown in the on position.

Referring to the drawings, wherein like characters of reference denote corresponding parts in the several views, the invention, as it is exemplifled thereiir is comprised essentially of a unitary assembly ofmanual and automatic switching devices mountedon-a two-part case, together with certainxpower' line and working circuit terminals,

suitably-interconnected for the accomplishment of the stated objects and purposes of the invention. e

The case-is comprisedin a base part or section III and a top part or section I2, both made of porcelainor other dielectric material and normally securedtogether by screws I 4. The case may be associated with a wall switch plate IS:

A metal (Figure 1),,if.its installation permits. mounting strip 18 is secured to the outer or'top face of the top case part or section l2, byscrews 20, and it'also serves as a retainer for an actuating lever 22', of a main control switch.

Themain control switch, in addition to the actuated lever 22, is comprised in a movable switch element 24, both of which are mounted within the top case part or section IZfor rocking movements, acoi-led spring26 being interposed between them to transmit-the motion of the lever 22 to the switch element 24, to cause thelatter to snap alternately to on and o positions. In one of these positions, the switch element 2 bridges a pair of stationary contacts 23 and 3d, and in the other, a pair of stationary contacts 32 and 34, bothpairs of thecontacts being mounted on the outer or upper side of the top case part or sec tioni2.

:Mountedbmthe inner or upper side of the base part or section ill of the case, to one side of its transverse center, is the movable contact element 36, preferably of leaf spring form, and an associated stationary contact 38, of an auxiliary manual control switch, preferably of the pushbutton type, an actuating member 46 being mounted for reciprocatory motion in the top case part or section 12 (Figures 1, 2 and 4), to close the movable contact 36 on the stationary contact 38, when it is depressed.

Seated within a depression 42, formed centrally of t as part or section In of the case, are a pair of magnetic coils 44, of an automatic switch device, of relay form, which, when energized, actuate an armature 46 to close a movable contact element 48 on a stationary contact 50, the movable contact preferably taking the form of a leaf spring secured at one end, as at 52, and having an iron bar, constitutin the armature 46, secured crosswise thereof, in line with the cores of the magnetic coils 44.

. Positioned on the base part or section III of the case, at the opposite side of the transverse center thereof, is a thermostatic switch, which is comprised in a movable contact element 54, having the form of a leaf spring secured at one end, as at 56, and its other end bearing on an adjustable member 58 carried in a bracket 60 (Figures 5, 7 and 8). Cooperative with the movable contact 54, is a thermostatic element 62, that is preferably in the form of a bimetallic bar, made up of juxtaposed strips of steel and brass, and is secured at one end, as at 64, with its free end normally engaged with the movable contact 54. Associated with the thermostatic bar 62, is a heating element 66, that may take the form of a coil of resistance wire encircled about the bar and insulated therefrom, one end of element or coil being in electrical connection with the bar, at the point of its securement 64.

Mounted in the top case part or section I2, to one side of its longitudinal center, is a pair of power line terminals 68, and 10 (Figures 1 and 6), which are to be connected by power line leads L and L respectively, while at the opposite side of the longitudinal center thereof, is a pair of circuit terminals 12 and 14, said terminals being respectively in electrical connection with the stationary contacts 36, 34, 28 and 32.

The electrical connections between the several power line and working circuit terminals 68, l0, l2 and i4, and the contacts of the above described switching devices, and as shown in Figure '7, are as follows: The circuit terminal 12 is in electrical connection with the stationary contact 28, of the main control switch, and is also connected by a wire 16 to the movable contact 36, of the auxiliary control switch. Underlying the free ends of the movable contacts 36 and 48 (Figure 5), respectively of the auxiliary switch and the relay, is a metal strip or plate 18, which carries the stationary contacts 38 and 58 (Figures 7 and 8), and is electrically connected by a wire 80 to the stationary contact 30, of the main control switch, which contact 36 is in electrical connection with the power line terminal 68. The movable contact 36, of the auxiliary control switch, is connected bya wire 82 to the secured end 52 of the movable contact 48, of the relay 44, to which end, one lead from the relay coils is also connected, as at 84 (Figures 5, 7 and 8), while the other end of the latter is connected, as at 86, to the secured end of the movable contact 54, of the thermostatic switch. The remaining terminal oi the heating coil 68 is connected by a 4 wire 88 to the circuit terminal 14, which is in electrical connection with the stationary contact 32, of the main control switch.

In the use of this form of the interval switch, power line leads L and L are connected to the terminals 68 and 10, respectively, while a wire 93 connects the terminal 10 to one side of an electrical device, e. g., the lamp 92, and a wire 84, the terminal 12 to the opposite side of the device or lamp 92, placing the latterin parallel with the other of the switch circuits, substantially as shown in Figure 7. Here, to light the lamp 92 so that it will remain lit until the switch lever 22 is again manually operated, the lever 22 is moved to on position, when the switch element line lead L by way of terminal 16, wire 96, lamp 92, wire 94, terminal 12, stationary contact 28, switch element 24, stationary contact 30, to the terminal 68 and the power line lead L To put out the lamp 92, the circuit is opened by moving the lever 22 to oil position, when the switch element 24 will be snapped by the action of the coiled spring 26 into bridging relation with the stationary contacts 32 and 34. In this operation of the main control switch, the circuit remains broken at the contacts 36, 38, of the auxiliary switch and at the contacts 48, 50, of the relay 44, which pairs of contacts are in parallel with each other.

To light the lamp S2 for a short interval, at the end of which, it will be automatically extinguished and remain so, the lever 22 will be left in the stated off position, with the switch element 24 in bridging relation with the stationary contacts 32 and 34. Now, by depressing the pushbutton 40, the movable contact 36, of the auxiliary control switch, will close on the stationary contact 38, and current will then flow from the power line lead L by way of terminal 10, stationary contact 34, switch element 24, stationary contact 32, terminal l4, wire 88, heating coil 66, thermostatic element 62, movable contact 54, lead 36, relay coils 44, wire 82, movable contact 36, stationary contact 38, wire 80 to terminal 68 and the power line lead L With the momentary closing of the push-button contacts 36, 38, the current flowing through the relay coils 44 causes the armature 46 to be magnetically attracted and its movement closes the movable contact 48 on the stationary contact 50, when the current will be shunted about the push-button contacts 36, 38, through the relay contacts 48, 50, conductor (strip or plate) 78, wire 80, to termi-' nal 68 and the power line lead L Here, current will also flow from the powerline lead L by way of terminal 16, wire 90, lamp 92, wire 94, terminal 12, wires 16, 82, to the secured end 52 of the movable contact 48, of the relay 44, where it passes with the current flowing through the relay coils to the power line lead L by way of the stationary contact 50, conductor (strip or plate) 18, wire 86 and terminal 68. The current flowing through the resistance coil 66 causes it to heat up and, in turn, to heat the bimetallic bar 62, causing the latter to break the circuit at the movable contact 54. With the breaking of the circuit at this point, the relay coils 44 are deenergized and release the armature 46, which results in the movable contact 48 breaking the circuit at the stationary contact 56. When the bimetallic bar 62 cools, it returns to its normal position, closing the circuit through the resistance coil 66, at the contact 54, the circuit, however, remaining open atthe relay contacts 48, 50, until the push-button switch contacts 36, 38, are again momentarily closed.

In the circuit arrangement shown in Figure 8, the switch devices and the lamp 92' are in series with the power line leads L and L the lead L here being directly connected with one side of the device or lamp 92' and the wire 94', from the opposite side thereof, to the terminal 16. while a wire 96 will connect the terminal 14 with terminal 68, to which the power line lead L is connected. Also, the wire 80, leading from the conductor (strip or plate) 18' (Figure 8), will be connected to the terminal 12. Here, with the lever 22 set to "on position, placing the switch element 24 in bridging relation with the stationary contacts 32, 34, of the main control switch, current will flow from the power line lead L direct to the device or lamp 92' and, from thence, by way of wire 94, terminal 18, stationary contact 34, switch element 24, stationary contact 32, terminal 14, wire 96, to terminal 68 and the power line lead L Now, the lamp 92 will be lighted and will remain so, until the lever 22 is manipulated to off position, causing the coiled spring 26 to snap the switch element 24 into bridging relation with the stationary contacts 28 and 36, when it will be extinguished. In the latter position of the switch element 24, the circuit is set for interval operation and, here, current will flow from the power line lead L by way of the device or lamp 92, wire 94, terminal I8, wire 88', resistance coil 66, contacts 62, 54, relay coils 44, wire 82, to the movable contact 36, of the push-button switch and, upon the actuation of the latter to close the movable contact 86 on the stationary contact 38, it will flow through wire 80 to the terminal 12, stationary contact 28, switch element 24, stationary contact 36, to terminal 68 and the power line lead L With the closing of the push-button contacts 36, 38, the relay coils 44 will be energized and magnetically attract the armature 46, causing the movable contact 48 to close on the stationary contact 50, when the current will be shunted from the wire 82' through the latter contacts and will pass by way of conductor (strip or plate) 18, wire 80, terminal 12, stationary contact 28, switch element 24, stationary contact 30, terminal 68, to power line lead L Again, with the heating up of the resistance coil 66, the circuit on the device or lamp 92' will be broken at the contacts 54 and 62, of the thermostatic switch, followed by the tie-energizing of the coils 44 and the opening of the contacts 48 and 50, of the relay.

If while the switch is set for interval opera tion, it is desired to open the circuit before the contacts 54 and 62, of the thermostatic switch. and the contacts 48 and 50,'of the relay, open thereof is subject to any and all changes in structural details and circuit arrangements that may fall within the scope of the appended claims.

I c aim:

1. In a switch structure of the class described, a main control switch having two positions for closing a circuit on a current source, in one of such positions, the current source is connected directly with an electrical device for its continued operation until the main control switch is set to the other of the positions thereof, and in the latter position of the main control switch, the current source is indirectly connected with said electrical device through automatic switchin means and an auxiliary control switch, said automatic switching means being made operative upon the momentary closing of said auxiliary control switch to shunt the current about the auxiliary control switch and connect it with said electrical device, said automatic switching means operating after an elapsed period of time to open the circuit on said current source. I

2. In a switch structure of the class described, a main control switch having two circuit closing positions, an auxiliary control switch, a relay and an automatic switching means, said switches automatically, the lever 22 is moved to the on position and then back to its "oil position.

Having thus fully described my invention, it

is to be understood that the disclosed embodiment being electrically interconnected with a current source and an electrical device to be controlled, said main control switch being manually operable to one of its circuit closing positions to connect said current source directly with said electrical device for its continued operation until the main control switch is set to the other of its circuit closing positions, said auxiliary control switch being manually and momentarily operable to connect said current source to said relay and said automatic switching means, said relay operating to shunt the current from said source about said auxiliary control switch and to pass it through said automatic switching means to said electrical device, following the opening of said auxiliary control switch, said automatic means operating after an elapsed time period to open the circuit on said current source for rendering said relay and said electrical device inoperative.

3. The invention as in claim 2, with said main control switch having the form of a double pole, double throw, snap type, and including a movable switch element adapted to bridge each of the pole pairs in its alternate directional movements, one pole of each pair being in connection with one lead oi a power line and one pole of each pair in connection with a circuit to be controlled.

GEORGE SPEER.

REFERENCES CITED The following references are of record in the file oi. this patent:

UNITED STATES PATENTS Number Name Date 1,297,945 Warden et a1. Mar. 18, 1919 1,335,709 Bjcrnsen Mar. 30, 1920 

